As a countermeasure against global warming, power generation systems using natural energy such as wind power are attracting great attention.
Some power generation systems using wind power include a wind mill rotated by wind such that a torque of the wind mill drives a power generation motor to generate electric power. Other power generation systems using wind power include a piezoelectric element attached to a board vibrated by wind such that vibrations of the board deform the piezoelectric element to generate electric power. See “Wind power generation, Introduction for beginners”, [online], [Search: Mar. 25, 2010], <URL: http://windhp.seesaa.net/article/111301162.html>.
However, the foregoing power generation systems using wind mills or vibrating boards have many problems. For instance, when newly installing such power generation systems, an installation site must be selected. Additionally, it is costly to install the wind mill or the vibrating board.